Père-Lachaise is the celebrity cemetery - it has almost anyone French, talented and dead that you care to mention. Not even French, for that matter. Creed and nationality have never prevented entry: you just had to have lived or died in Paris or have an allotted space in a family tomb.

Devout King Louis IX (St Louis, 1226-70) had a hobby of accumulating holy relics. In the 1240s, he bought what was advertised as the Crown of Thorns, and ordered Pierre de Montreuil to design a shrine. The result was Sainte-Chapelle. With 15m (49ft) windows, the upper level appears to consist almost entirely of stained glass. The windows depict hundreds of scenes from the Old and New Testaments, culminating with the Apocalypse in the rose window.

This immense pseudo-classical building was constructed by Azéma, Boileau and Carlu for the 1937 international exhibition, with giant sculptures of Apollo by Henri Bouchard, and inscriptions by Paul Valéry. The Palais houses the Musée National de la Marine and the Musée de l'Homme (closed for renovation until 2012). In the east wing are the Théâtre National de Chaillot and the Cité de l'Architecture et du Patrimoine.

Loved by the Surrealists, this solitary Flamboyant Gothic belltower with its leering gargoyles is all that remains of St-Jacques-La-Boucherie church, built for the powerful Butchers' Guild in 1508-22. The statue of Blaise Pascal at the base commemorates his experiments on atmospheric pressure, carried out here in the 17th century. A weather station now crowns the 52m (171ft) tower.

The Conciergerie looks every inch medieval. However, much of the façade was added in the 1850s, long after Marie-Antoinette, Danton and Robespierre were imprisoned here during the Revolution. The 13th-century Bonbec tower, the 14th-century César and Argent towers, and the Tour de l'Horloge all survive from the Capetian palace.The visit takes you through the Salle des Gardes and the Salle des Gens d'Armes, an impressive vaulted Gothic hall built between 1301 and 1315 for Philippe 'le Bel'.

Despite it’s elegant, Belle Époque allure the ‘Little Palace’ is overshadowed by its big brother, Le Grand Palais, just across the road. But ignore it and you’ll miss out on one of Paris’s loveliest fine arts museums, with an extensive mish-mash of works by Poussin, Doré, Courbet and the impressionists, as well as other paintings and sculptures from the Antiquity to 1900. The building, built by Charles Girault for the 1900 for the World Fair, is lit entirely by natural light and sits around a pretty little garden - a plum spot for coffee and cakes.

Paris's first planned square was commissioned in 1605 by Henri IV and inaugurated by his son Louis XIII in 1612. With harmonious red-brick and stone arcaded façades and steeply pitched slate roofs, it differs from the later pomp of the Bourbons. Laid out symmetrically with carriageways through Pavillon de la Reine on the north side and Pavillon du Roi on the south, the other lots were sold off as concessions to officials and nobles (some façades are imitation brick). It was called place Royale prior to the Napoleonic Wars, when the Vosges was the first region to pay its war taxes.

104, described as a 'space for artistic creation', occupies a vast 19th-century building on the rue d'Aubervilliers that used to house Paris's municipal undertakers. The site was saved from developers by Roger Madec, the mayor of the 19th, who's made its renovation the centrepiece of a massive project of cultural and urban renewal.There aren't any constraints on the kind of work the resident artists do: 104 is open to 'all the arts', but finished pieces have to shown in one of 104's annual 'festivals'.

Some distance removed from the Arabic-speaking inner-city enclaves of Barbès and Belleville, this vast Hispano-Moorish construct is nevertheless the spiritual heart of France's Algerian-dominated Muslim population. Built from 1922 to 1926 with elements inspired by the Alhambra and the Bou Inania Medersa in Fès, the Paris mosque is dominated by a stunning green-and-white tiled square minaret. On la rue Geoffroy-St-Hilaire, La Mosquée café (open 9am-midnight daily) is delightful - a modest courtyard with blue-and-white mosaic-topped tables shaded beneath green foliage.

The Paris observatory was founded by Louis XIV's finance minister, Colbert, in 1667; it was designed by Claude Perrault (who also worked on the Louvre), with labs and an observation tower. The French meridian line drawn by François Arago in 1806 (which was used here before the Greenwich meridian was adopted as standard) runs north-south through the centre of the building. You'll need to apply for an appointment at the Observatoire by letter, but it's also worth checking the website for openings linked to astronomical happenings - or visit on the Journées du Patrimoine.